Thread-cutting and thread-end-holding device for embroidery sewing-machines



J. LINDSAY. THREAD CUTTING AND THREAD END HOLDING DEVICE FOR EMBROIDERYSEWING MACHINES.

APPLICATION FILED MAY I3, I9I=8-. 1,373,747. Patented Apr. 5, 1921.

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m mam Y J. LINDSAY. THREAD CUTTING AND THREAD END'HOLDING DEVICE FOREMBROIDERY SEWING MACHINES. APPLICATION FILED MAY 13. l9l8.

73,747. Patented Apr. 5, 1921,

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JOHN LINDSAY, OF LUIRGAN, IRELAND, ASSIGNOR OF ONE-THIRD TO WILLIAMHENRY EVANS BROWN AND ONE-THIRD TO JAMES BELL, BOTH OF LURGAN, IRELAND.

THREAD-CUTTING AND THREAD-END-I-IOLDING DEVICE FOR EMBROIDERY SEWING-MACHINES.

Specification of Letters Patent. Patented Apr. 5, 1921.

Application filed May 13, 1918. Serial No. 234,279.

To all whom it may concern.

Be it known that. 1, JOHN LINDSAY, of Queen street, Lurgan, Ireland, asubject of the King of Great Britain and Irelanchhave invented certainnew and useful Improve- ;ments Relating to Thread-Cutting and 1 provedmeans for cutting the threads above and below the material on which thesewing operation is being done, the cutting of the thread beingefi'ected when the sewing operation has been completed at one part andit is desired to commence another sewing operation at a different placeon the article being sewn.

The invention is particularly applicable to machine sewn embroidery, andlike work, in which, at present, when one figure or portion of a patternor design has been sewn, the upper and under threads are drawn alongwith the article on which the sewing is being done, to the point atwhich the next sewing operation is to be comumenced, and, so on, untilthe pattern or design has been completed, the portions of the threadbetween the various figures of the design having to be subsequently cutaway. This invention obviates such subsequent cutting away or clipping,of the threads, thereby saving the cost of this operation and alsosaving the thread.

Under my invention the thread cutting means for embroidery and the likesewing machines is characterized by the cutting of the upper and underthreads being effected by cutting mechanism which is brought into actionon the completion of any particular sewing operation and is providedwith safety locking means whereby the cutting mechanism can only beoperated when the sewing needle is free of the cloth and alsocharacterized by the mechanism for cutting the upper thread being causedto seize the thread above the cutting point and to hold same after thecutting operation and until several stitches have been made by thesewing mechanism whereby the cut thread is prevented from being drawnout of the eye of the needle by the take up mechanism, means being alsoprovided to draw off the under thread ahead of the cutting operation 1norder to insure a sufficiency of thread below the cutting blade to takeup the starting stitches of the next sewing operation.

In order that the invention may be clearly understood I have hereuntoappended eX- planatory drawings, whereon, by way of illustration ofexample, the invention is shown applied to a l/Vheeler and lVilson'sewing machine adapted for embroidery work. Figure 1 is a backelevation of the sewlng machine with my improvements applied theretowith the upper portion of the needle bar and appertaining parts brokenoff and shown separately in Fig. 1

Fig. 2 is a cross sectional elevation on the line 00, as, Fig. 1 andlooking in the di rection of the arrow y.

Fig. 3 is an elevation looking on the driving end of the machine withthe driving pulley removed to more clearly show the locking devices.

Fig. 4 is a detail plan V16W*Of the upper thread cuttingshears andshowing them in the'out of action position.

Fig. 4: is a perspective view of the cutting shears in the out of actionposition as shown in Fig. 4.

Fig. 5 is a detail view corresponding to Fig. 4t but showing the cuttingshears in the position which they occupy after cutting the upper thread.

Figs. 6 and 6 are detail views of the In carrying out the invention, asshown in the drawings, I provide a lever member 1 pivotally carried onthe frame 2 of the machine, being connected therewith at the pivot point3. The end 1 of the lever 1 is connected with a vertically slidable bart connected with a foot treadle or equivalent (not shown) whereby theend 1 of the lever 1 can be pulled down against the action of a spring5. A downward movement of the lever end 1 causes its end 1 (shown brokenoff) to be correspondingly raised. The end 1 of the lever 1 is connectedwith the presser foot lifting mechanism, being engaged ina slot in avertically slidable bar 6 which connects with the presser bar 7 in suchmanner that the raising of the bar 6 by the end 1 of the lever 1 willeffect a raising of the presser foot bar and so raise the presser feetof the machine. The raising of the end 1 of the lever 1 also pressesback the cam-shaped end 8 (see also Fig. 2) of a lever 8 pivotallyconnected, at 8 with the machine head 9. This lever 8 is made, at itsother end 8, with a slot 8 which, when the end 8 is pressed backward, asabove described, is caused to come into the path of movement of a springcatch 10 provided at the top of the needle bar. 11. The needle bar 11has a sleeve 11 surrounding it and connected directly with the needleoperating mechanism, and the needle bar 11 can be connected with anddisconnected from this sleeve 11 by means of the spring clutch or catch10 which has a hook 10 adapted to engage a projection 11 at the top ofthe needle bar sleeve 11. While the machine is sewing, the hook 10 ofthe spring catch 10 remains in engagement with the projection 11 on theneedle bar sleeve and so efiects the reciprocation of the needle bar 11and needle 12. When, however, the lever 1 is operated for the purpose ofactuating the cutting mechanism as hereinafter described, it isnecessary that the needle should be held up clear of the cloth. For thispurpose the catch 10 comes into operation to disconnect the needle bar11 from its operating sleeve 11 by the raising of the end 1 of the lever1, causing a forward movement of the end 8 of the lever 8 whereby theslot 8 therein is caused to engage the backwardly projecting portion 10of the catch 10 sothat the catch 10, and the needle bar 11 connectedtherewith, are prevented from descending while the sleeve 11 continuesin action during the thread cutting operation. Connected with the lever8, at 8, is an end 13 of another lever 13 which is pivotally connectedwith the machine :head at 13 and has its other end 13 connected with theupper end 14 of a member 1 1- which, at its lower end 1 1 carries theupper thread cutting shears. The

member 14; is turnably supported on. a bracket 15 projecting from thebar 7 which carries the presser feet 7 and 7 and, atfthe lower end 149,the member 14 has a plate 14 pivotally connected to it and to which thecutting shears 15 and 15 (Figs. 1 1 and 5) are pivotally connected. Thecutting shears 15 and 15 extend forward on each side of'the presser footbar 7 and needle 12. When the shears 15 and 15 are moved back, by theraising of the front 7 end 1 of the lever 1, to the position immediatelyabove the needle hole in the throat plate, the cutting members 15 and 15of the shears are also moved toward one another from the position shownat Figs. 1 and 4 to the position shown at Fig. 5 this movement beingobtained from a bar 16 which passes through thepresser bar 7 and has, atits lower end, arms 16 and 16 carrying pins 16 and 16 which engage inslots 15 and 15 in the shear members 15 and. 15 The upper end of the bar16 is cranke-.. as shown at Fig. 2 and the cranked end 16 is connectedby a link 17 with a member 18 pivotally connected with the lever 1 at 18and projecting above the lever 1 andhaving a slot or opening. 18therein. bar 16 is turned to efiect the cutting of the thread, theportion 15 of the cutting mem-' ber 15 pushes the thread under thecutting edge 00 and draws off a certain amount into the jaws of thecutting member 15 (Fig. 4) and after the cutting operation has takenplace by the meeting of the cutting edges 22, m the upper thread is heldbetween the members 15, 15 above the cutting point so long as theshearing members 15 and 15 remain in the position shown at Fig. 5.Immediately after the cuttingoperation the shears 15 and 15 close withthe upper thread held between the meeting edges of the cutting members15 and 15 to prevent the take up drawing the thread out of the eye ofthe needle, until a number of stitches have been made by the sewingmechanism. This holding of the upper thread is effected by a catch 19which is pivotally connected at 19 with the plate 20 and has, atits end19 a projecting pin 19. This pin 19 is capable of being engaged in theopening 18. of the member- 18 on the lever 1 and, when it is inengagement therewith, the shears 15 and 15 are closed, with themembers15 and 15 holding the upper thread. The opening 18 in the member 18allows the latter to move in the direction of the arrow 2 (Fig. 1) underthe action of a spring 21. This movement of the member 18 effects acorresponding movement of the link 17 and cranked bar 16 whereby thepins 16 and 16 are turned in such manner as to close the shearingmembers 15%. and 15 and so cause the portion 15* to coiiperate with thecutting member 15 to hold the upper thread so long as the pin 19 remainsin the opening 18. In order to hold the upper thread, after the cuttingoperation, and to release it when the predetermined number of stitcheshave been sewn, a slidably supported ratchet member 22 is providedhaving slots 22 and 22 engaging pins 19 and 19 on the catch 19. When themachine is running and the cutting device is not in act on the pm 19 ofthe catch 19 will bein the position shown at Fig. 1 and the ratchetmember 22 will be out of engagement with the pawls and 24; when,however, the cutting mechanism has been operated and the end 1 of thelever 1 has been lowered so that the pin 19engages in the opening 18 inthe member 18, the raising of the lever end 1 will bring the When theteeth of the ratchet member 22 into engagement with the pawls 23 and24:. This upward movement of the member 19 is effected against theaction of a spring 26. The pawl 23 is connected with the stud 25 of thecross over cam and the usual oscillation of the stud 25 causes the pawl23 to move the ratchet member 22 toward the member 18 by a step-by-stepmovement, corresponding to the number of stitches required to be madebefore the release of the upper thread from the shearing members and, incompleting this movement, the ratchet member 22 will tilt over themember 18 until the pin 19 is clear of the opening 18 whereupon thespring 26 will pull down the member 19 to the position shown at Fig. 1and the re-action of the spring on the member 18 will cause same to openthe shear members 15 and 15 so as to release the thread. During theforward movement of the ratchet member 22 the pawl 24 holds the ratchetmember and prevents it moving back when the pawl 23 is lifted at eachoscillation of the stud 25. The ratchet member 22 moves forward againstthe action of a spring 27 which re-acts to pull back the ratchet member22 when the pin 19 has dropped clear of the opening 18 as abovedescribed.

In order to prevent the possibility of the cutting mechanism beingoperated, when the needle is in the cloth, I provide an automaticlocking device as shown at Figs. 1 and 3. This locking device consistsof a cam member 28 secured on the machine shaft 29 and adapted to act ona locking member 30 having a portion 30 which normally projects under aportion 1 at the end 1 of the lever 1 so as to lock same except at suchtimes as the cam 28 moves the locking member 30 clear of the part 1 ofthe lever 1. The cam 28 is arranged to move the lever member 30 clear ofthe part 1 when the take up is at its highest point with the needleclear of the cloth. I also provide a locking lever 31 which has aportion 31- normally under the projecting part 1 of the lever 1 so as toprevent the operating of the lever 1 and cutting mechanism but which, bya pull on its end 31*, can be moved by the operator so as to be clear ofthe part 1 of the lever 1 in order to allow of the cutting mechanismbeing operated when required. The end 31 of the locking lever 31 wouldbe connected to a suitable operating treadle or equivalent. A spring 32keeps the locking member 30 in contact with the cam 28 and a spring 31keeps the locking lever 31 normally in the locked position.

The under thread is cut simultaneously with the upper thread, orslightly later, by means of a cutting blade 33 which cooperates with acutting edge or cutting portion 3 1 on the underside of the throat plate34. This cutting blade 33 is actuated by the ting operation is adaptedto push the thread ahead of the cutting edge 33 and to draw offsuflicient thread below the shearing point to provide a sufficiency ofunder thread for the starting stitches at the next sewing operation.

Although I have described the cutting mechanism as operated by the footit may be operated by hand or by the knee.

Having now fully described my invention what I claim and desire tosecure by Letters Patent is 1. In or for sewing machines for doingembroidery or like work on cloth, cutting mechanism for cutting theupper and lower sewing threads, means connected with the pressure bar ofthe machine, for operating said upper thread cutting mechanism, meansfor operating said under thread cutting mechanism, and a pivotal catchand sliding member whereby the upper thread, after being cut, is heldand prevented from being drawn out of the eye of the machine needleuntil several stitches have been made by the machine.

2. Thread sewing devices for embroidery sewing machines comprising alever pivoted to the head of the machine, a lever connected with thefirst mentioned lever and connected with another lever supported by thepressure bar of the machine, a plate on the last mentioned lever, a pairof horizontally disposed levers pivotally supported on the plate, threadcutting and holding devices for the upper thread carried by thehorizontally disposed levers and means whereby 'the operation of thelevers to efiect the cutting of the thread is prevented except when theneedle of the machine is clear of the cloth.

3. In or for sewing machines for doing embroidery or like work on cloth,cutting mechanism for cutting the upper and lower sewing threadscomprising upper cutting blades, means for operating same, an undercutting blade, means for operating same, means preventing the bladesoperating when the needle is in the cloth and an extension .on the undercutting blade for drawing oil? a sufficiency of thread for the startingstitches of the next sewing operation.

In testimony whereof I aflix my signature in presence of two witnesses.

JOHN LINDSAY. Witnesses:

ANDREW HAMILTON, J orm Knox.

